Redis Rails

Introduction to Redis Rails

Redis rails are the storage driver of redis that was used to implement active fragment caching and action dispatch of API for session storage. There are several reasons why we use redis with rails. In our rails application, we also use the redis database. As we know, redis provides an in-memory data structure, so data kept in memory is stored in redis.

Key Takeaways

• Rails is a popular framework that is used to build applications. However, if our application grows in size, we will face scaling issues.
• By using it we can use the new feature name cache which is supported by rails version 5.2.

What are Redis Rails?

There are multiple tools we can use but we are adding different technologies to our application which increases the complexity of the redis database server. We are using redis in-memory data structure for storing the multi-purpose tool for solving multiple problems.

We need to install redis in our system for using rails with redis. As we know that redis is a database of a key-value store, this database is primarily known as a primary database for the queue, message broker, and cache. The cache of redis will deliver response time in milliseconds which enables the real-time application very useful to us.

How to Use Redis Rails in a Database?

The below steps show how we can use the redis rails in a database as follows:

1. In the first step we are installing the ruby in our system. We can see that we are installing the same by using the apt command.

Code:

apt install ruby

Output:

2. By using gem install we can connect to the redis server by using the redis-cli command as follows.

Code:

redis-cli

Output:

3. After connecting to the server, now we are opening the gemfile for adding the below code. In the below code, we are adding the key as follows.

Code:

require 'js'
redis_rails = Redis.new(host: "localhost")
redis_rails.set("p", 1)
redis_rails.get("p")

Output:

4. By using redis rails we can also work with the documentation in the below example we are using the incr command as follows.

Code:

redis_rails.incr("p")
redis_rails.setex("redis rails", 20, 50)
redis_rails.get("redis rails")

Output:

5. We can also use the sorted set in the redis database. The redis is allowing us to create a sorted set of values as follows.

Code:

redis_rails.zadd ("color", 20, "Black")
redis_rails.zadd ("color", 20, "White")
redis_rails.zadd ("color", 30, "Pink")

Output:

Redis Rails Installation and Configuration

As we know that redis will support various data structures like lists, hashes, strings, sorted sets, bitmap, and many more. For using the redis with ruby rails we need to first install and configure the same.

Below steps shows how we can install and configure the redis rails as follows:

1. In the below example we are installing the redis server by using the apt command as follows. If we are using linux then we can install the same by using the yum command.

Code:

apt install redis

Output:

To use it we require the redis database. Basically, without using rails we are installing the redis server by using the apt command but in the below example, we are installing the same by using the gem command.

Code:

gem install redis

Output:

2. To use the redis server we can start the same by using the below command. We are starting the redis database server.

Code:

redis-server

Output:

3. After starting the redis server we are installing the ruby rails by using the apt command.

Code:

apt install ruby

Output:

4. After installing the ruby rails now we are opening the gemfile and adding the below code as follows.

Code:

gem 'redis'
gem 'redis-namespace'
gem 'redis-rails'

Output:

5. After editing the gemfile now in this step we are creating the environment file to connect the application of rails easily.

Code:

DB = "redis"
URL = redis://127.0.0.1
PORT = 6379

Output:

6. Now we are telling our redis application to connect to the redis by using a specified initializer as follows.

Code:

Redis.current = Redis.new(url:  ENV['URL'],
port: ENV['PORT'],
db:   ENV['DB'])

Output:

7. After creating the dedicated initializer now we are opening the configuration file and making the below changes as follows.

Code:

dev:  adapter: async
redis_test:  adapter: testing
prod:  adapter: redis
url: <…>
channel_prefix: app_prod

Output:

8. After changing the configuration file, now in this step we are adding the following to the configuration file as follows.

Code:

S_URL = redis://master/1
S_HOSTS = slave-1 slave-2 slave-3
S_PORT=26379

Output:

Redis Rails Caching

Basically, caching means storing the content and reusing the same at the time of responding same requests. Caching is important to boost the performance of the application. By using caching our website is running on a single server and handling multiple requests. The below example shows how we can use the caching redis as follows.

Code:

config.cache_store = : redis, {
expires_in: 3.hour,
namespace: 'cache',
redis: { host: 'localhost', port: 6379, db: 'redis' },
}

Output:

In the below example, we are creating the class and same class we are using redis rails caching as follows.

Code:

class Event < app
def tik
Rails.cache.fetch ([cache_key, __method__], expires_in: 10.minutes) do
tik.count
end
end
def t_sum
Rails.cache.fetch ([cache_key, __method__]) do
tik.sum (:amt)
end
end
end

Output:

Redis Rails Sorted Sets

As we know that redis is not a limited key-value storage database, it also offers some data structures. It allows us to create a list of items that have been sorted using the specified values. The sorted value is known as the score in the documentation of redis. In the below example, we are querying the top N items as follows. We are using the zadd command to use sorted sets.

Code:

redis.zadd ("letter", 20, "A")
redis.zadd ("letter", 30, "B")
redis.zadd ("letter", 40, "C")

Output:

In the below example, we have created the set query on tom letter as follows.

Code:

r.zrevrange ("letter", 0, 0)

Output:

FAQ

Given below are the FAQs mentioned:

Q1. Why are we using sorted sets in ruby on rails?

Answer: Basically, redis provides an in-memory data store architecture. Redis will keep data in memory, so we use sorted sets in redis.

Q2. What is the use of redis rails?

Answer: Ruby on rails is a framework that is used to create and develop applications. We can solve the application scaling challenges by using it.

Q3. What is text documentation in redis rails?

Answer: We are using the text documentation in redis rails. We can also use the incr command to define the text documentation.

Conclusion

There are multiple tools we can use but we are adding different technologies to our application which increases the complexity of the redis database server. It is the driver of storage of redis which is used to implement the caching support of active fragments and action dispatch of API for session storage.

Recommended Articles

This is a guide to Redis Rails. Here we discuss the introduction, how to use redis rails in a database. installation and configuration. You may also have a look at the following articles to learn more –

1. Redis Get All Keys
2. Redis GUI
3. Redis Pubsub
4. Redis Version